Substituted pyrazolylpyrazole derivative and use of same as herbicide

ABSTRACT

Provided is a compound capable of effectively control worst weeds of higher leaf stages that present practical problems. A specific pyrazolylpyrazole derivative of formula (1) is disclosed that is able to solve the above-mentioned problems.

TECHNICAL FIELD

The present invention relates to a substituted pyrazolylpyrazolederivative and the use of that compound as an herbicide.

BACKGROUND ART

Numerous herbicides have recently come to be used in the cultivation ofagricultural crops, and have contributed to reduced labor for farmersand improved productivity of agricultural crops. Numerous herbicides arealso used practically in the cultivation of field and paddy rice.

However, there is considerable diversity in the species of weeds, thegermination and growth periods of each species of weed are not uniform,and the growth of perennial weeds extends over a long period of time.Consequently, it is extremely difficult to control all weeds with asingle spraying of herbicide.

Early to mid-term one-shot herbicides have been shown to be effectivefor paddy rice by treating during the second to third leaf stage ofpaddy weeds (generic term for Echinochloa oryzicola, Echinochloacrus-galli var. crus-galli, Echinochloa crus-galli var. formosensis,Echinochloa crus-galli var. praticola and Echinochloa crus-galli var.caudata), and major weeds can be controlled by a single treatment (seeNon-Patent Document 1). However, it is extremely difficult to controlpaddy weeds that have grown to the 3.5 leaf stage or more with early tomid-term one-shot herbicides currently in practical use, and the controlof paddy weeds in the third leaf stage and control of paddy weeds in the3.5 leaf stage are technically completely different.

Moreover, maintaining herbicidal effects (residual activities) over along period of time is important in terms of reducing spraying ofagricultural chemicals, saving on labor and curtailing costs, and isconsidered to be an essential area of performance for early to mid-termone-shot herbicides.

In addition, acetolactate synthase (ALS) inhibitors have come to bewidely used in recent years, and weeds exhibiting resistance to ALSinhibitors have become a problem. There are few herbicides demonstratingadequate efficacy against ALS inhibitor-resistant biotypes of theperennials of Sagittaria trifolia and Sagittaria pygmeae. In addition,examples of perennial weeds that have caused problems in recent yearsinclude Eleocharis kuroguwai, Scirpus planiculmis and Scirpusnipponicus, while examples of annuals include Aeschynomene indica,Leptochloa chinensis and Murdannia keisak, and there are few herbicidesthat demonstrate adequate efficacy against these difficult-to-controlweeds.

On the other hand, numerous pyrazole derivatives are used practically asherbicides, and although pyrazole derivatives such as4-(2,4-dichlorobenzoyl)-1,3-dimethyl-5-pyrazolyl p-toluenesulfonate(common name: “Pyrazolate”),2-[4-(2,4-dichlorobenzoyl)-1,3-dimethylpyrazol-5-yloxy]acetophenone(common name: “Pyrazoxyfen”) or2-[4-(2,4-dichloro-m-toluoyl)-1,3-dimethylpyrazol-5-yloxy]-4′-methylacetophenone (common name: Benzofenap”) are widely used, their registeredapplication range for paddy weeds in Japan when used alone is up to the1.5 leaf stage, and although these pyrazole derivatives are effectiveagainst a wide range of weeds, the efficacy thereof is not alwaysadequate against paddy weeds of higher leaf stages.

In addition, although Compound 73 of Example 4 described in PatentDocument 1 in the form of1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl) 5-[methyl(prop-2-ynyl)amino]pyrazole-4-carbonitrile (common name: “Pyraclonil”) iseffective against a wide range of weeds, its efficacy against paddyweeds of higher leaf stages is inadequate, and the registeredapplication range in Japan against paddy weeds when using this herbicidealone is up to the 1.5 leaf stage.

CITATION LIST Patent Literature Document

-   Patent Document 1: WO 94/08999

Non-Patent Literature Document

-   Non-Patent Document 1: “Suiden Zasso no Seitai to Sono    Bojo-Suitosaku no Zasso to Josozai Kaisetsu (Ecology of Paddy Weeds    and their Control—Explanation of Weeds of Rice Paddy Crops and    Herbicide)”, p. 159

SUMMARY OF THE INVENTION Technical Problem

An object of the present invention is to provide a herbicide compositionthat has a wide herbicidal spectrum, is able to control worst weeds ofhigher leaf stages that present practical problems, and not causephytotoxicity to crops such as paddy rice.

Solution Problem

As a result of conducting extensive studies to achieve theaforementioned object, the inventors of the present invention found thata pyrazolylpyrazole derivative having a specific chemical structureexhibits a wide herbicidal spectrum over a long period of time,demonstrates superior herbicidal efficacy against worst weeds of higherleaf stages, and has adequate safety with respect to cultivated crops,thereby leading to completion of the present invention on the basis ofthese findings.

A compound represented by the following formula (I):

wherein,

R¹ represents a halogen atom,

R² represents a cyano group or nitro group,

R³ represents a hydrogen atom, trifluoroacetyl group,pentafluoropropionyl group or heptafluorobutenyl group,

R⁴-R⁶ may be the same or different and represent hydrogen atoms, halogenatoms, C₁-C₆ alkyl groups (which may be substituted with one or morehalogen atoms depending on the case), C₃-C₆ cycloalkyl groups (which maybe substituted with one or more halogen atoms depending on the case),C₁-C₆ alkoxy(C₁-C₆)alkyl groups (which may be substituted with one ormore halogen atoms depending on the case) or phenyl groups (which may besubstituted with one or more halogen atoms, nitro groups, cyano groups,C₁-C₄ alkyl groups (which may be substituted with one or more halogenatoms depending on the case) or C₁-C₄ alkoxy groups),

a represents 3 to 5, and

b represents 0 to 2

(excluding compounds in which R¹ represents a chlorine atom, R²represents a cyano group, R³-R⁶ represent hydrogen atoms and b is 1).

Preferably,

in formula (I),

R¹ represents a chlorine atom or bromine atom,

R⁴-R⁶ may be the same or different and represent hydrogen atoms, halogenatoms, C₁-C₆ alkyl groups (which may be substituted with one or morehalogen atoms depending on the case), C₃-C₆ cycloalkyl groups, C₃-C₆alkoxy(C₁-C₆)alkyl groups or phenyl groups, and

a represents 4.

More preferably,

in formula (I),

R¹ represents a chlorine atom,

R² represents a cyano group,

R⁴-R⁶ may be the same or different and represent hydrogen atoms, halogenatoms or C₁-C₆ alkyl groups (which may be substituted with one or morehalogen atoms depending on the case), and

b represents 1.

In the present description,

a description in the manner of the previous “C_(a)-C_(b)” of eachsubstituent refers to the number of carbon atoms respectively present inthat group being from a to b.

Fluorine atoms, chlorine atoms, bromine atoms and iodine atoms areincluded in “halogen atoms”.

An “alkyl group” can be linear or branched, and although there are nolimitations thereon, examples thereof include methyl, ethyl, n- oriso-propyl, n-, iso-, sec- or tert-butyl, n-pentyl and n-hexyl groups,and each is selected within a range of the specified number of carbonatoms thereof.

An “alkoxy group” refers to an alkyl-O-group in which the alkyl moietyhas the above-mentioned meaning, and although there are no limitationsthereon, examples thereof include methoxy, ethoxy, n- or iso-propoxy,n-, iso-, sec- or tert-butoxy groups, and each is selected within arange of the specified number of carbon atoms thereof.

Although there are no limitations on “cycloalkyl group”, examplesthereof include cyclopropyl, cyclobutyl, cyclopentyl and cyclohexylgroups, and each is selected within a range of the specified number ofcarbon atoms thereof.

In the case of the “alkyl group”, “alkoxy group” and “cycloalkyl group”,at least one hydrogen atom contained in these groups may be substitutedwith a halogen atom, and although there are no limitations thereon,examples thereof when using the example of an alkyl group includechloromethyl, dichloromethyl, trifluoromethyl, chloroethyl,dichloroethyl, trifluoroethyl, tetrafluoropropyl, bromoethyl,bromopropyl, chlorobutyl, chlorohexyl and perfluorohexyl groups, andeach of these is selected within a range of the specified number ofcarbon atoms thereof.

In the case where the aforementioned group or moiety is substituted witha plurality of halogen atoms or a phenyl group is substituted with aplurality of halogen atoms, nitro groups, cyano groups, C₁-C₄ alkylgroups (which may be substituted with one or more halogen atomsdepending on the case) or C₁-C₄ alkoxy groups, that group can besubstituted with more than one halogen atoms and/or substituents thatare the same or different.

In addition, the cis form and trans form are included in cases of thepresence of geometrical isomers. Although the present invention includescompounds represented by formula (I), it also relates to all geometricalisomers and mixtures thereof not specifically defined.

In all of the formulas listed below, substituents and symbols have thesame meanings as defined in formula (I) unless specifically definedotherwise. Among the compounds of formula (I) provided by the presentinvention, compounds in which R³ is a hydrogen atom can be easilysynthesized by an alkylation reaction of a compound represented byformula (II).

Compounds in which R³ does not contain a hydrogen atom can besynthesized by a perfluoroamidation reaction represented by thefollowing formula (III).

The compound of formula (II) can be synthesized fromtetrahydro-2H-pyran-2-ylideneacetonitrile or 5-chlorovaleryl chloride inaccordance with the methods described in WO 93/10100 and WO 94/08999.

The compound represented by formula (II) can be synthesized by analkylation reaction per se with reference to known reaction conditions(see, for example, WO 94/08999). This may also be carried out by aprocedure consisting of protection of the amino group followed byalkylation and deprotection depending on the case.

The perfluoroamidation reaction per se of formula (III) can be easilycarried out under known reaction conditions and a known method describedin the literature cited therein (for example, Japanese PatentApplication Laid-open No. 2005-154420).

The compound of formula (I) provided by the present invention hassuperior herbicidal efficacy and is useful as a herbicide as is clearfrom the results of the herbicidal activity tests described in TestExamples 1 to 3 to be subsequently described.

The compound of formula (I) of the present invention has activityagainst numerous types of crop weeds and non-crop weeds. Examples ofcultivated plants include gramineous plants such as rice, wheat, barley,corn, oats or sorghum, broadleaf crops such as soybeans, cotton, beets,sunflowers or rapeseed, fruit trees, vegetables such as fruitvegetables, root vegetables or leafy vegetables, and grasses, and thecompound of formula (I) can be used for the cultivation thereof.

The compound of the present invention has herbicidal efficacy againstthe various weeds listed below that cause problems in rice paddies inany of the treatment methods of soil treatment in an irrigated orunirrigated state, soil incorporation treatment and foliar treatment.Although the following lists examples thereof, these weeds are notlimited to the following examples.

Examples of paddy weeds that can be controlled by the compound offormula (I) of the present invention include Alismataceous weeds such asAlisma canaliculatum, Sagittaria trifolia or Sagittaria pygmaea,Cyperaceous weeds such as Cyperus difformis, Cyperus serotinus, Scirpusjuncoides, Eleocharis kuroguwai, Scirpus planiculmis or Scirpusnipponicus, Scrophulariaceous weeds such as Lindernia procumbens,Lindernia dubia subsp. dubia or Lindernia dubia, Pontederiaceous weedssuch as Monochoria vaginalis or Monochoria korsakowii, Potamogetonaceousweeds such as Potamogeton distinctus, Lythraceous weeds such as Rotalaindica or Ammannia multiflora, Asteraceous weeds such as Bidenstripartita or Bidens frondosa, Leguminoseous weeds such as Aeschynomeneindica, Commelinaceous weeds such as Murdannia keisak, and Gramineousweeds such as Echinochloa oryzicola, Echinochloa crus-galli var.crus-galli, Echinochloa crus-galli var. formosensis, Echinochloacrus-galli var. praticola, Echinochloa crus-galli var. caudata,Leptochloa chinensis, Leersia japonica, Paspalum distichum or Leersiaoryzoides.

In addition, the compound of the present invention has herbicidalefficacy against the various weeds listed below that cause problems infield land and non-crop land in any of the treatment methods of soiltreatment, soil incorporation treatment and foliar treatment. Althoughthe following lists examples thereof, these weeds are not limited to thefollowing examples.

Examples thereof include broadleaf weeds, including Solanaceous weedssuch as Solanum nigrum or Datura stramonium, Malvaceous weeds such asAbutilon avicennae or Sida spinosa, Convolvulaceous weeds such asIpomoea pupurea, Amaranthaceous weeds such as Amaranthus lividus,Asteraceous weeds such as Xanthium strumarium, Ambrosiaartemisiilifolia, Galinsoga ciliata, Cirsium arvense, Senecio vulgarisor Stenactis annuus, Brassicaceous weeds such as Rorippa indica, Sinapisarvensis or Capsella bursa-pastoris, Polygonaceous weeds such asPersicaria longiseta or Fallopia convolvulus, Portulacaceous weeds suchas Portulaca oleracea, Chenopodiaceous weeds such as Chenopodium album,Chenopodium ficifolium or Kochia scoparia, Caryophyllaceous weeds suchas Stellaria media, Scrophulariaceous weeds such as Veronica persica,Commelinaceous weeds such as Commelina communis, Lamiaceous weeds suchas Lamium amplexicaule or Lamium purpureum, Euphorbiaceous weeds such asEuphorbia supina or Euphorbia maculata, Rubiaceous weeds such as Galiumspurium, Galium spurium var. Echinospermon or Rubia argyi, Violaceousweeds such as Viola mandshurica, and Leguminoseous weeds such asSesbania exaltata or Cassia obfusitolia, and Gramineous weeds such asSorghum bicolor, Panicum dichotomiflorum, Sorghum halepense, Echinochloacrus-galli var. crus-galli, Digitaria ciliaris, Avena fatua, Eleusineindica, Setaria viridis, Alopecurus aequalis or Poa annua, andCyperaceous weeds such as Cyperus rotundus.

Moreover, the compound of the present invention is also able to controla wide range of weeds growing in mowed swaths, fallow land, orchards,grasslands, lawn grass plots, train line caps, vacant land and forestland, or on farm roads, causeways and other non-crop land.

Moreover, the compound of formula (I) of the present invention does notdemonstrate phytotoxicity that becomes a problem for paddy rice in thecase of any cultivation method such as direct seeding cultivation ortransplantation cultivation of paddy rice.

The compound of formula (I) of the present invention can be appliedbefore or after plant germination and can be mixed into soil beforeseeding.

Although the dosage of the compound of formula (I) of the presentinvention can be varied over a wide range corresponding to the type ofcompound, type of target plant, application window, location ofapplication, properties of desired effects and the like, and as ageneral reference thereof, the dosage can be within the range of about0.01 g to 100 g, and preferably about 0.1 g to 10 g, as the amount ofactive compound per are.

Although the compound of formula (I) of the present invention can beused alone, a formulation assistant and the like is normallyincorporated in the compound of formula (I) in accordance with ordinarymethods, and although there are no limitations thereon, it is preferablyformulated and used in any arbitrary drug form such as a dustablepowder, emulsifiable concentrate, oil miscible liquid, solubilizingagent, suspo-emulsion, fine granule, aerosol spray, less drifting dust,micro granule fine, fine grains F, granules, wettable powder, waterdispersible granules, flowable concentrate, throw-in types (Jumbo),tablets, paste, emulsion in oil, water soluble powder, water solublegranule, soluble concentration or capsule suspension.

There are no limitations on formulation assistants able to be used forformulation, and examples include solid vehicles, liquid vehicles,binders, thickeners, surfactants, anti-freezing agents andpreservatives.

Examples of solid vehicles include, but are not limited to, talc,bentonite, montmorillonite, clay, kaolin, calcium carbonate, sodiumcarbonate, sodium bicarbonate, mirabilite, zeolite, starch, acidic clay,diatomaceous earth, chaoite, vermiculite, slaked lime, vegetable powder,alumina, activated carbon, sugars, hollow glass, silica sand, ammoniumsulfate and urea.

Examples of liquid vehicles include, but are not limited to,hydrocarbons (such as kerosene or mineral oil), aromatic hydrocarbons(such as toluene, xylene, dimethyl naphthalene or phenyl xylyl ethane),chlorinated hydrocarbons (such as chloroform or carbon tetrachloride),ethers (such as dioxane or tetrahydrofuran), ketones (such as acetone,cyclohexanone or isophorone), esters (such as ethyl acetate, ethyleneglycol acetate or dibutyl maleate), alcohols (such as methanol,n-hexanol or ethylene glycol), polar solvents (such asN,N-dimethylformamide, dimethylsulfoxide or N-methylpyrrolidone) andwater.

Examples of binders and thickeners include, but are not limited to,dextrin, sodium salts of carboxymethyl cellulose, polycarboxylicacid-based polymer compounds, polyvinylpyrrolidone, polyvinyl alcohol,sodium lignin sulfonate, calcium lignin sulfonate, sodium polyacrylate,gum arabic, sodium alginate, mannitol, sorbitol, bentonite-based mineralmatter, polyacrylic acid and derivatives thereof, chaoite and naturalsugar derivatives (such as xanthan gum or guar gum).

Examples of surfactants include, but are not limited to, anionicsurfactants such as fatty acid salts, benzoates, alkylsulfosuccinates,dialkylsulfosuccinates, polycarboxylates, alkyl sulfate ester salts,alkyl sulfates, alkyl aryl sulfates, alkyl diglycol ether sulfates,alcohol sulfate ester salts, alkyl sulfonates, alkyl aryl sulfonates,aryl sulfonates, lignin sulfonates, alkyl diphenyl ether disulfonates,polystyrene sulfonates, alkyl phosphate ester salts, alkyl arylphosphates, styryl aryl phosphates, polyoxyethylene alkyl ether sulfateester salts, polyoxyethylene alkyl aryl ether sulfates, polyoxyethylenealkyl aryl ether sulfate ester salts, polyoxyethylene alkyl etherphosphates, polyoxyethylene alkyl aryl phosphate ester salts or salts ofnaphthalene sulfonate-formalin condensates, and nonionic surfactantssuch as sorbitan fatty acid esters, glycerin fatty acid esters, fattyacid polyglycerides, fatty acid alcohol polyglycol ethers, acetyleneglycol, acetylene alcohol, oxyalkylene block polymers, polyoxyethylenealkyl ethers, polyoxyethylene alkyl aryl ethers, polyoxyethylene styrylaryl ethers, polyoxyethylene glycol alkyl ethers, polyoxyethylene fattyacid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethyleneglycerin fatty acid esters, polyoxyethylene hydrogenated castor oil orpolyoxypropylene fatty acid esters.

Examples of anti-freezing agents include, but are not limited to,ethylene glycol, diethylene glycol, propylene glycol and glycerin.

Examples of preservatives include, but are not limited to, benzoic acid,sodium benzoate, methyl paraoxybenzoate, butyl paraoxybenzoate,isopropyl methyl phenol, benzalkonium chloride, chlorhexidinehydrochloride, aqueous hydrogen peroxide, chlorhexidine gluconate,salicylic acid, sodium salicylate, zinc pyrithione, sorbic acid,potassium sorbate, dehydroacetic acid, sodium dehydroacetate,phenoxyethanol, isothiazoline derivatives such as5-chloro-2-methyl-4-isothiazolin-3-one or 2-methyl-4-isothiazolin-3-one,2-bromo-2-nitropropane-1,3-diol and salicylic acid derivatives.

The previously mentioned solid vehicles, liquid vehicles, binders,thickeners, surfactants, anti-freezing agents and preservatives can eachbe used alone or in a suitable combination thereof corresponding to thepurpose of use and the like.

Although the incorporated ratio of the compound of formula (I) of thepresent invention with respect to the total herbicide composition of thepresent invention can be increased or decreased as necessary and thereare no particular limitations thereon, it is normally about 0.01% byweight to 90% by weight, and for example, in the case of being in theform of a dustable powder or granules, is preferably about 0.1% byweight to 50% by weight and more preferably about 0.5% by weight to 10%by weight, while in the case of being in the form of an emulsifiableconcentrate, wettable powder or water dispersible granules, ispreferably about 0.1% by weight to 90% by weight and more preferablyabout 0.5% by weight to 50% by weight.

These preparations can be provided for use in various types ofapplications by diluting to a suitable concentration as necessaryfollowed by spraying or applying directly to plant foliage, soil or thesurface of a rice paddy and the like.

The following provides an explanation of the present invention throughexamples thereof.

EXAMPLES Example 1 Method for the Synthesis of1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-5-(2-methylprop-2-enylamino)pyrazole-4-carbonitrile(Compound 1)

Acetonitrile (75 ml) was added to5-amino-1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)pyrazole-4-carbonitrile(19.7 g) followed by slowly dropping acetyl chloride (5.8 g) therein andrefluxing for 5 hours. Following completion of the reaction, water wasadded to the reaction mixture and the precipitated solid was washed withethyl acetate to obtainN-(1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-4-cyanopyrazol-5-yl)acetamide(12 g).

N-(1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-4-cyanopyrazol-5-yl)acetamide(2.5 g) was dissolved in acetonitrile (8 ml) followed by the addition ofpotassium carbonate (1.3 g) and stirring. 3-chloro-2-methyl-1-propene(0.8 g) was then added thereto followed by refluxing for 8 hours.Following completion of the reaction, water was added to the reactionmixture followed by extraction with ethyl acetate. After drying withsodium sulfate, the solvent was concentrated under reduced pressure andthe resulting solid was purified by silica gel column chromatography(hexane/ethyl acetate=1:1). The purified compound (1.3 g) was dissolvedin ethanol (3 ml) followed by the addition of sodium hydroxide (0.14 g)and water (1 ml) and reacting for 1 day at room temperature. Followingcompletion of the reaction, water was added to the reaction liquid andthe precipitated solid was washed with isopropyl ether to obtain thedesired compound (0.8 g).

Example 2 Method for the Synthesis of1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-5-(2-chloroprop-2-enylamino)pyrazole-4-carbonitrile(Compound 2)

Formic acid (18.4 g) was slowly dropped into acetic anhydride (33.7 g)cooled to 5° C. followed by stirring for 2 hours at 60° C. (ReactionMixture A). Separate from the above,5-amino-1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)pyrazole-4-carbonitrile(26.3 g) was dissolved in acetonitrile (200 ml) and stirred. Thepreviously prepared Reaction Mixture A was slowly dropped therein andreacted for 1 day at room temperature and then for 4 hours at 60° C.Subsequently, the solvent was concentrated under reduced pressurefollowed by neutralizing using aqueous potassium carbonate solution,washing the precipitated solid with water and drying to obtainN-(1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-4-cyanopyrazol-5-yl)formamide(28 g).

N-(1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-4-cyanopyrazol-5-yl)formamide(1.5 g) was dissolved in acetonitrile (5 ml) followed by addingpotassium carbonate (0.8 g) and stirring. 2,3-dichloro-1-propene (0.6 g)was slowly dropped therein and reacted for 3 hours at 40° C., andfollowing completion of the reaction, water was added to the reactionmixture followed by extraction with ethyl acetate. After drying withsodium sulfate, the solvent was concentrated under reduced pressure andthe crude product was purified by silica gel column chromatography(hexane/ethyl acetate=1:1) to obtainN-(1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-4-cyanopyrazol-5-yl)-N-(2-chloroprop-2-enyl)formamide(1.73 g).

N-(1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-4-cyanopyrazol-5-yl)-N-(2-chloroprop-2-enyl)formamide(1.73 g) was dissolved in ethanol (5 ml) followed by the addition of 10%hydrochloric acid (6.9 g) and stirring for 3 hours at room temperature.Following completion of the reaction, water was added to the reactionmixture and the precipitated solid was filtered out and dried to obtainthe desired compound (4.1 g).

Example 3 Method for the Synthesis of(N-1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-4-cyanopyrazol-5-yl)-N-(2-chloroprop-2-enyl)-2,2,2-trifluoroacetamide(Compound 3)

1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-5-(2-chloroprop-2-enyl)pyrazole-4-carbonitrile(0.7 g) was dissolved in acetonitrile (5 ml) followed by slowly droppingin trifluoroacetic anhydride (1.3 g). After stirring for 7 days at 40°C., saturated aqueous sodium hydrogen carbonate solution was added tothe reaction liquid followed by extracting with ethyl acetate. Afterdrying with sodium sulfate, the solvent was distilled off under reducedpressure and the resulting crude product was purified by silica gelcolumn chromatography (hexane/ethyl acetate=4:1) to obtain the desiredcompound (0.4 g).

The starting material in the form of the compound of formula (II) wassynthesized in accordance with WO 93/10100 and WO 94/08999.

The examples listed in the following tables can be synthesized by thesame manner as the above-mentioned methods or obtained in the samemanner as the above-mentioned methods.

TABLE 1

Compound R¹ R² R³ R⁴ R⁵ R⁶ cis/trans a b mp Refractive index (° C.) 1 ClCN H CH₃ H H 4 1 97-98 2 Cl CN H Cl H H 4 1 123-124 3 Cl CN COCF₃ Cl H H4 1 95-96 4 Cl CN H H Ph H trans 4 1 127-128 5 Cl CN H H H H 4 2 130-1316 Cl CN H F F F 4 2 111-112 7 Cl CN H H Cl H cis 4 1 126 8 Cl CN H H ClH trans 3 1 9 Cl CN H H Cl H cis 3 1 10 Cl CN H H Cl H trans 4 1 11 ClCN H Cl Cl H mix 4 1 125-126 12 Cl CN H H CH₃ H mix 4 1 114-115 13 Cl CNH H CH₃ CH₃ 4 1 75-76 14 Cl CN H H CH₃ H mix 4 2 15 Cl CN H H CH₃ H mix3 1 16 Cl CN COCF₃ H Ph H mix 4 1 100 17 Cl CN COCF₃ H H H 4 1 91-92 18Cl CN COCF₃ H H H 4 2 1.5270(22.9) 19 Cl CN COCF₃ CH₃ H H 4 1 85-86 20Cl CN COCF₃ F F F 4 2 21 Cl CN COCF₃ H Cl H cis 4 1 90-91 22 Cl CN COCF₃H Cl H trans 4 1 23 Cl CN COCF₃ Cl Cl H mix 4 1  99-100 24 Cl CN COCF₃ HCH₃ H mix 4 1 108-109 25 Cl CN COCF₃ H CH₃ CH₃ 4 1 67-68 26 Cl CN COCF₃H CH₃ H mix 4 2 27 Cl CN COCF₃ H CH₃ H mix 3 1 28 Cl CN COC₂F₅ H H H 4 11.5074(28.1) 29 Cl NO₂ H H H H 4 2 30 Cl NO₂ H Cl H H 4 1 150 31 Cl NO₂H CH₃ H H 4 1 91-92 32 Cl NO₂ H H Cl H cis 4 1 147-148 33 Cl NO₂ H Cl ClH mix 4 1 154-156 34 Cl NO₂ H H CH₃ H mix 4 1 102-103 35 Cl NO₂ H H CH₃CH₃ 4 1 82-83 36 Cl NO₂ COCF₃ H H H 4 1 85 37 Cl NO₂ COCF₃ H H H 4 266-67 38 Cl NO₂ COCF₃ CH₃ H H 4 1 116-117 39 Cl NO₂ COCF₃ H Cl H cis 4 180 40 Cl NO₂ COCF₃ H CH₃ H mix 4 1 102-103 41 Cl NO₂ COCF₃ H CH₃ CH₃ 4 172-73 42 Br CN H H H H 4 2 129-130 43 Br CN H Cl H H 4 1 129-130 44 BrCN H CH₃ H H 4 1 105-106 45 Br CN H H Cl H cis 4 1 105-106 46 Br CN H ClCl H mix 4 1 137-138 47 Br CN H H CH₃ H mix 4 1 120-121 48 Br CN H H CH₃CH₃ 4 1 83-84 49 Br CN COCF₃ H H H 4 1 107-108 50 Br CN COCF₃ H H H 4 270-71 51 Br CN COCF₃ Cl H H 4 1 107-108 52 Br CN COCF₃ CH₃ H H 4 1 85 53Br CN COCF₃ H Cl H cis 4 1 102-103 54 Br CN COCF₃ Cl Cl H 4 11.5480(25.0) 55 Br CN COCF₃ H CH₃ H mix 4 1 70-71 56 Br CN COCF₃ H CH₃CH₃ 4 1 1.5308(26.4) 57 Br NO₂ H H CH₃ H mix 4 1 105-106 58 Br NO₂ COCF₃H H H 4 1 99 59 Br NO₂ COCF₃ H CH₃ H mix 4 1 103-104

Preparation Examples 1. Dustable Powder

Compound of formula (I) 10 parts by weight Talc 90 parts by weight

A dustable powder is obtained by mixing the above components and finelycrushing with a hammer mill.

2. Wettable Powder

Compound of formula (I)   10 parts by weight Polyoxyethylene alkyl arylether sulfate 22.5 parts by weight White carbon 67.5 parts by weight

A wettable powder is obtained by mixing the above components and finelycrushing the mixture with a hammer mill.

3. FLOWABLE CONCENTRATE

Compound of formula (I) 10 parts by weight Polyoxyethylene alkyl etherphosphate 10 parts by weight Bentonite  5 parts by weight Ethyleneglycol  5 parts by weight Water 70 parts by weight

A flowable concentrate is obtained by mixing the above components andcrushing using a wet pulverizer.

4. Emulsifiable Concentrate

Compound of formula (I) 15 parts by weight Ethoxylated nonylphenol 10parts by weight Cyclohexanone 75 parts by weight

An emulsifiable concentrate is obtained by mixing the above components.

5. Granules

Compound of formula (I) 5 parts by weight Calcium lignin sulfonate 3parts by weight Polycarboxylate 3 parts by weight Calcium carbonate 89parts by weight 

The above components are mixed followed by adding water, kneading,extruding and granulating. Subsequently, granules are obtained by dryingfollowed by sizing.

Biological Testing Examples 1. Paddy Herbicidal Activity Test

Rice paddy soil was filled into a 1/10000 are pot followed by theaddition of suitable amounts of water and chemical fertilizer, kneading,seeding with Echinochloa crus-galli, Monochoria vaginalis and Scirpusjuncoides and maintaining in an irrigated state at a water depth of 3cm.

Wettable powder of Target Compound (I) shown in Table 1 prepared incompliance with the preparation examples were diluted with a suitableamount of water, rice plants in the 2.0 leaf stage were transplantedduring 3.5 leaf stage of Echinochloa crus-galli, and treated by droppingin chemical in the prescribed amount per are using a pipette.

After treating for 30 days in a glass greenhouse at an averageatmospheric temperature of 30° C., the herbicidal efficacy thereof wasinvestigated.

Evaluation of herbicidal efficacy was carried out by comparing growthinhibition rate (%) with an untreated group, while evaluation ofphytotoxicity was carried out by comparing growth inhibition rate (%)with the state of a complete eradication group, and were evaluated at 11levels indicated below.

0 (exponent): 0% to less than 10% (growth inhibition rate)

1: 10% to less than 20%

2: 20% to less than 30%

3: 30% to less than 40%

4: 40% to less than 50%

5: 50% to less than 60%

6: 60% to less than 70%

7: 70% to less than 80%

8: 80% to less than 90%

9: 90% to less than 100%

10: 100%

The results are shown in Table 2.

Control agent 4.59 (described in WO 94/08999)

Control agent 4.75 (described in WO 94/08999)

Control agent 4.85, 4.156 (described in WO 94/08999)

Control agent 4.239 (described in WO 94/08999)

TABLE 2 5g^(a.i.)/10a 1g^(a.i.)/10a Echinochloacrus- Monochoria ScirpusRice Echinochloacrus- Monochoria Scirpus Rice Compound galli vaginalisjuncoides plants galli vaginalis juncoides plants 1 9 8 9 0 8 7 9 0 2 98 9 0 9 7 9 0 3 10 8 9 0 9 7 9 0 5 10 8 9 1 9 7 9 0 6 9 8 8 1 9 8 7 0 79 8 9 0 9 7 9 0 11 9 8 9 0 8 7 8 0 12 10 9 10 1 9 8 9 0 13 10 8 9 1 9 88 0 17 10 9 8 1 9 9 8 0 18 9 8 9 1 9 7 8 0 19 10 8 9 0 9 7 9 0 20 9 8 90 9 8 8 0 21 9 10 9 0 9 8 9 0 23 9 8 9 0 8 7 8 0 24 10 9 9 1 9 8 8 0 2510 8 9 1 9 8 9 0 26 9 8 9 0 9 7 8 0 28 9 9 10 0 9 8 8 0 30 10 10 10 0 98 9 0 31 9 8 9 0 9 7 9 0 32 9 10 10 1 8 8 9 0 34 9 8 9 0 9 8 9 0 35 9 1010 1 9 8 9 0 36 10 9 9 1 9 8 8 0 39 10 8 8 1 9 8 7 0 40 9 8 8 0 8 7 8 042 9 8 8 0 8 8 7 0 45 9 9 9 1 9 9 9 1 46 8 8 8 1 7 7 7 0 47 10 8 9 0 9 78 0 48 9 8 10 1 8 7 8 1 49 9 9 9 1 8 8 7 1 50 10 8 9 1 9 7 7 0 51 9 8 80 9 8 8 0 53 10 8 8 1 9 7 7 1 57 10 8 9 0 9 7 8 0 4.59 5 4 4 2 2 2 2 14.75 4 2 5 1 3 2 4 0 4.85, 4.156 3 1 3 2 2 0 1 2 4.239 5 1 2 1 3 0 1 0

2. Farming Soil Treatment Test

Field soil was filled into a 1/6000 are pot followed by seeding withDigitaria ciliaris, Chenopodium album and Amaranthus retroflexus andcovering with soil.

Wettable powder of compounds of formula (I) shown in Table 1 prepared incompliance with the preparation examples were diluted with water to theprescribed amount of chemical and uniformly sprayed onto each soilsurface layer using 10 liters of sprayed water per are prior to weedgrowth following seeding.

After treating for 30 days in a glass greenhouse at an averageatmospheric temperature of 30° C., the herbicidal efficacy thereof wasinvestigated.

Evaluation of herbicidal efficacy is carried out in the same manner asthe above-mentioned Test Example 1.

The results are shown in Table 3.

TABLE 3 10g^(a.i.)/10a 5g^(a.i.)/10a Digitaria Chenopodium AmaranthusDigitaria Chenopodium Amaranthus Compound ciliaris album retroflexusciliaris album retroflexus 3 10 10 10 10 10 10 12 10 10 10 10 10 10 2110 10 10 10 10 10 24 10 10 10 10 10 10 30 10 10 10 10 10 10 32 10 I0 1010 10 10 4.59 6 6 6 5 5 5 4.75 4 6 6 3 5 6 4.85, 4.156 4 5 6 3 4 3 4.2395 3 5 4 2 3

3. Weed Foliar Treatment Test

Soil was filled into a 1/6000 are pot followed by seeding with Digitariaciliaris, Chenopodium album and Amaranthus retroflexus, covering withsoil, and cultivating in a glass greenhouse at an average atmospherictemperature of 25° C.

Wettable powder of Target Compound (I) shown in Table 1 prepared incompliance with the preparation examples were diluted with water to theprescribed amount of chemical and uniformly sprayed onto the weeds using15 liters of sprayed water per are when Digitaria ciliaris had grown tothe 1.0 to 2.0 leaf stage.

After treating for 3 weeks in a glass greenhouse at an averageatmospheric temperature of 25° C., the herbicidal efficacy thereof wasinvestigated.

Evaluation of herbicidal efficacy was carried out in the same manner asthe above-mentioned Test Example 1.

The results are shown in Table 4.

TABLE 4 10g^(a.i.)/10a 5g^(a.i.)/10a Digitaria Chenopodium AmaranthusDigitaria Chenopodium Amaranthus Compound ciliaris album retroflexusciliaris album retroflexus 3 10 10 10 10 10 10 12 10 10 10 10 10 10 2110 10 10 10 10 10 24 10 10 10 10 10 10 30 10 10 10 10 10 10 32 10 10 1010 10 10 4.59 6 7 7 4 6 6 4.75 5 7 7 4 6 5 4.85, 4.156 5 6 6 3 5 4 4.2395 4 6 3 3 4

INDUSTRIAL APPLICABILITY

According to the present invention, the compound for formula (I) of thepresent invention is useful as a herbicide against harmful plants sinceit has superior herbicidal efficacy against undesirable plants.

1. A compound represented by the following formula (I):

wherein, R¹ represents a halogen atom, R² represents a cyano group ornitro group, R³ represents a hydrogen atom, trifluoroacetyl group,pentafluoropropionyl group or heptafluorobutenyl group, R⁴-R⁶ may be thesame or different and represent hydrogen atoms, halogen atoms, C₁-C₆alkyl groups which may be substituted with one or more halogen atomsdepending on the case, C₃-C₆ cycloalkyl groups which may be substitutedwith one or more halogen atoms depending on the case, C₁-C₆alkoxy-C₁-C₆-alkyl groups which may be substituted with one or morehalogen atoms depending on the case or phenyl groups which may besubstituted with one or more halogen atoms, nitro groups, cyano groups,C₁-C₄ alkyl groups which may be substituted with one or more halogenatoms depending on the case or C₁-C₄ alkoxy groups, a represents 3 to 5,and b represents 0 to 2 excluding compounds in which R¹ represents achlorine atom, R² represents a cyano group, R³ to R⁶ represent hydrogenatoms and b is
 1. 2. The compound according to claim 1, wherein R¹represents a chlorine atom or bromine atom, R⁴-R⁶ may be the same ordifferent and represent hydrogen atoms, halogen atoms, C₁-C₆ alkylgroups which may be substituted with one or more halogen atoms dependingon the case, C₃-C₆ cycloalkyl groups, C₃-C₆ alkoxy-C₁-C₆-alkyl groups orphenyl groups, and a represents
 4. 3. The compound according to claim 1,which is represented by formula (I), wherein R¹ represents a chlorineatom, R² represents a cyano group, R⁴-R⁶ may be the same or differentand represent hydrogen atoms, halogen atoms or C₁-C₆ alkyl groups whichmay be substituted with one or more halogen atoms depending on the case,and b represents
 1. 4. A herbicide composition containing a herbicidallyeffective amount of at least one type of the compound according toclaim
 1. 5. The herbicide composition according to claim 4, furthercontaining a formulation assistant.
 6. A method for control undesirableplants, comprising the step of applying an effective amount of at leastone type of the compound according to claim 1 to an undesirable plant orthe location of the undesirable vegetation.
 7. A use of the compoundaccording to claim 1 for control undesirable plants.
 8. The useaccording to claim 7, wherein the compound is used for controlundesirable plants among useful agricultural crops.
 9. A herbicidecomposition containing a herbicidally effective amount of at least onetype of the compound according to claim
 2. 10. A herbicide compositioncontaining a herbicidally effective amount of at least one type of thecompound according to claim
 3. 11. The herbicide composition accordingto claim 9, further containing a formulation assistant.
 12. Theherbicide composition according to claim 10, further containing aformulation assistant.
 13. A method for control undesirable plants,comprising the step of applying an effective amount of at least one typeof the compound according to claim 2 to an undesirable plant or thelocation of the undesirable vegetation.
 14. A method for controlundesirable plants, comprising the step of applying an effective amountof at least one type of the compound according to claim 3 to anundesirable plant or the location of the undesirable vegetation.
 15. Amethod for control undesirable plants, comprising the step of applyingan effective amount of the herbicide composition according to claim 4 toan undesirable plant or the location of the undesirable vegetation. 16.A method for control undesirable plants, comprising the step of applyingan effective amount of the herbicide composition according to claim 9 toan undesirable plant or the location of the undesirable vegetation. 17.A method for control undesirable plants, comprising the step of applyingan effective amount of the herbicide composition according to claim 10to an undesirable plant or the location of the undesirable vegetation.18. A method for control undesirable plants, comprising the step ofapplying an effective amount of the herbicide composition according toclaim 5 to an undesirable plant or the location of the undesirablevegetation.
 19. A method for control undesirable plants, comprising thestep of applying an effective amount of the herbicide compositionaccording to claim 11 to an undesirable plant or the location of theundesirable vegetation.
 20. A method for control undesirable plants,comprising the step of applying an effective amount of the herbicidecomposition according to claim 12 to an undesirable plant or thelocation of the undesirable vegetation.